diff --git a/tests/system_command/system_command.slt b/tests/system_command/system_command.slt
index fae1a11..7945aab 100644
--- a/tests/system_command/system_command.slt
+++ b/tests/system_command/system_command.slt
@@ -9,7 +9,7 @@ select read("${__TEST_DIR__}/test.txt")
 114514
 
 system ok
-echo 1919810 > ${__TEST_DIR__}/test.txt
+echo 1919810 > $__TEST_DIR__/test.txt
 
 query T
 select read("${__TEST_DIR__}/test.txt")